Fluorescent lamp flxture



Sept 59 195@ a1 KETELSEN -LZE FLUORESCENT LAMP FIXTURE Filed. June 3, 1946 3 Sheets-Sheet 2 I l I I N VEN TOR.

E. E Bye Kazza/Je.

Sept 59 i T. KETELSEN 52h22 FLUORESCENT LAMP FIXTURE Filed June 5 194e s sheets-sheet s 22 /p a 22k il Y lI E E. BY

Patented Sept. 5, 1950 UNITED STATES FATENT OFFICE l FLUORESCENT LAMP FIXTURE Tage Ketelsen, Detroit, Mich. Application June 3, 1946, Serial No. 673,950

6 Claims. l

This invention relates to fixtures for fluorescent lights and the like.

It is common practice, particularly in large or commercial buildings where the ceilings are high and e, relatively large area is to be lighted, to arrange fluorescent lamps end to end across the ceiling or wall. In order to satisfy specifications of the Fire Underwriters Association, the light fixtures must be fully enclosed, and, as presently fabricated, they are large and bulky. Consequently, the fixtures usually are mounted between and parallel to the joists or studs so that they can be set iiush with the ceiling or wall. As will be readily apparent, it is desirable to con-l ceal as much as possible of the fixtures, since they are made of unfinished sheet metal and consequently are relatively unsightly. If the xtures are mounted. across the joists or studs, the latter must be recessed or, alternatively, the oeiln ing or wall must be furred out iush with the box. Both alternatives are undesirable, since the rst greatly weakens the joists or studs and the latter is expensive. On the other hand, if the lighting arrangement is restricted to parallel mounting of the xtures, it is often difficult, if not impossible, to obtain proper light distribution.

Some fixtures have been developed for transverse or crosswise mounting, but they are relatively short and extend only between adjacent joists or studs. Consequently, they are not adaptable for commercial installations where long iiuorescent lamps are employed. Moreover, when this type of fixture is used, it is necessary to drill holes through the joists so that they can be connected in series and each hole must be iitted with a suitable insulating grommet. Not only is it a tedious and time-consuming task to drill. and fit these' holes, but they too weaken the joists or studs.

An important object oi the present invention is to provide a fluorescent lighting fixture which can be mounted either parallel to or across the jo-ists, without recessing or drilling the latter, and positioned flush with the ceiling in such manner that it need not be furred away from the joists.

Another object of the invention is to provide a fixture of the above-mentioned character that has provision for carrying the wiring across the joists and from one xture to another, thus eliminating the necessity of drilling and fitting the joists.

Still another object of the invention is to provide a fixture of the above-mentioned character (Cl. 24U-51.11)

in which all parts, except those emitting and reflecting light, are concealed after installation either adjacent to the ceiling or suspended a substantial distance therebelow without ma terially changing or aiecting the installation.

Other objects and advantages of the invention will be apparent during the course of the following description. y

In the drawings forming a part of this specication and wherein like numerals are employed to designate like parts throughout the same,

Fig. 1 is a perspective View showing one half of a fixture embodying the invention mounted across a plurality of ceiling joists;

Fig. 2 is a, fragmentary, longitudinal, sectional view of the partial fixture shown in Fig. 1 and showing the same extended to the left as viewed in the drawing;

Fig. 3 is a fragmentary, longitudinal, sectional View of the partial xture shown in Fig. l and illustrating the manner in which a second fixture is mounted end to end therewith;

Fig. 4 is an enlarged transverse, sectional view taken on the line ll--ll of Fig. 2;

Fig. 5 is an enlarged, transverse, sectional view taken on the line 5 5 of Fig. 2;

Fig. 6 is an enlarged, transverse, sectional view taken on the line 6-6 of Fig. 2;

Fig. 7 is an exploded perspective view of an electrical connector comprising a part of the invention; and v Fig. 8 is a diagrammatic and schematic view showing one complete fixture and fragmentary portions of two additional fixtures embodying the invention illustrating the complete fixture provided with two lamp-supporting covers and showing the manner in which a plurality of .fixtures can be connected in series and with lamp ymeans on the covers.k

Considered in certain of its broader aspects the iluorescent lighting fixture embodying the instant invention comprises a rough bo-x having one, two or more lamp-carrying covers. The rough box is formed from a series of sheet-metal housings which t between the joists and provide closures for the ballast and other electrical equipment in the lamp circuits. These housings are joined at the ends thereof by webs which extend over and are fastened to the joists. Attached to the sides of the housings and extending the full length of the rough box are sheet-metal strips which overlie the joists and -project downwardly therefrom a distance approximately equal to the thickness of plaster or other wall-forming material on or to be applied to the joists. At least one of these strips is fashioned to denne a channel which is open at its ends and along one side to provide a runway across the joists and through the wall for electrical supply lines in the rough box.

Thus the instant rough box is constructed so that the housings which accommodate the ballast and other bulky equipment in the fixture extend back between the joists, and no part of the box projects out farther than the side strips. Since these strips are just wide enough to extend through the ceiling plaster andY terminate flush therewith, the entire rough box, and wiring disposed therein, is concealed behind the ceiling. rIhe wiring in the channel is out of the Way but at the saine time readily accessible.

Each cover is equipped with mountings for a desired number of uorescent tube lainps and supports on its back surface suitable electrical apparatus which is adapted for connection to the supply lines in the rough box and transforms the usual 110- or 22m-volt current into electrical energy suitable for the lamps. According to the present invention the covers carry hinge straps which extend through slots in the rough box and normally project therefrom between the joists when the covers are fastened on the box. However, when the covers are removed and dropped for a short distance, hook portions on the hinge straps interlock with the ends of the slots and hold the covers, together with their adjuncts, suspended from the rough box and in such position that both it and the interior of the box are readily accessible. When the cover is fastened to the box, it is disposed substantially flush with the ceiling or wall, and only the outer surface of the cover, the lamps, and a portion of the mountings are visible.

Reference is now had to the accompanying by conventional stamping and forming operaif.

tions. They are fastened together in any suitable manner, as by welding, and collectively provide a strong, rigid receptacle 'or rough box for wiring and electrical apparatus in the tube light circuits.

Each of the housings I has a top IB which is integrally joined to spaced parallel side walls I8 and 2B, and the top and side walls have integral inturned end flanges 22. The top Vflanges preferably extend entirely across the housing, and the side flanges terminate short lof the lower or free edges of their respective side walls 'i8 and 2D. iThe projecting portions 24 of the side walls i8 and 2u define fastening means for the side wall strips I4 and actually need project only suflciently to attach to the latter. It is preferred, however, that portions 24 extend substantially the full width of strips I4, as shown in the drawing, to strengthen and reinforce the same.` Any desired number of these box-shaped housings may be used in making up a rough box, depending upon the nature of the fixture and the type of insulation. Six housings are incorporated in the rough box here shown by way 'of illustration, and the rough box is long enough to accommodate two covers placed end to end, each carrying a pair of fluorescent lamps. It is contemplated that rough boxes of different lengths and of various standard dimensions be made up as stock items so that the builder or contractor can select the boxes from stock according to the exigencies of the particular situation.

The connecting members I2 are generally U-shaped, as shown in Figs. 2 and 3, and each member which joins two of the housings I0 comprises a bottom 25 integrally connected to parallel walls 26 and 28. These walls are disposed in the housings I0 and are spot welded or otherwise attached to end anges 22. It will thus be apparent that the bottom walls 25 provide connecting Webs between the housings I0 and that the walls 26 and 28 provide end closures therefor. Each of the two end connecting members I2 are generally L-shaped, as shown in the right-hand portion of Fig. 3. The single upstanding wall 26 closes the endmost housing I0, and the bottom 25 defines a longitudinally extending terminal web for the rough box.

Each of the side-wall strips i4 has an opstanding flange 30 which is spot welded or otherwise attached tothe projecting side-wall portions 24. The flanges 3! extend the full length of the rough box and close the spaces or interstices between the portions 24 and below the webs 25. Formed integrally on the lower or outer edge of each flange 3B is an inturned under flange portion 32 which is bent back upon itself to provide an outer flange portion 34. Flange portions 32 and 34 preferably are spot welded together and provide a relatively stiff flange along each side of the rough box which strengthens and reinforces the same and provides convenient attaching members for the covers.

It is further contemplated that each rough box be equipped with electrical supply lines 36 which extendthe full length of the box. In this connection it will be observed that the inturned flanges 32, 34 denne a duct or runway for the supply lines 36, which ducts are open at their ends and at one side to permit easy insertion or replacement of the supply lines. Suitably shaped spring clips 3B are welded or otherwise aiiixed at spaced intervals to the upstanding flanges 3i) for removably holding supply lines 35 in the ducts. Two supply lines 36 are required and, in the instant embodiment of the invention, they are shown at opposite sides of the rough box; however, it will be readily apparent that, if desired, both supply lines can be mounted at one side of the box.

To facilitate connection of each fixture or the end fixture of a series electrically in the supply circuit of the building, each` Supply line 36 is equipped at one end (or, if desirable or necessary at both ends) with suitable electrical connectors 4c, which connectors are removably fastened in the ducts in the same manner as the supply lines 2S by suitably shaped clips 42 (Fig. 5). The electrical connectors 4D greatly facilitate and expedite installation ofthe fixtures and eliminate the necessity of soldering and taping the separate wirings in Vthe rough box and on the covers. As shown in Fig. 7, each connector 4l! comprises a solid metal body 44 which has a pair of countersunk sockets 46 in each end thereof and is provided with internally screw-threaded holes 48 each of which extends from one side of the body and opens into a respective one of the sockets. Entirely surrounding the body is a sheath or wrapper 50 of suitable electrically insulating mathrough the webs 25.

ames?,

terial, whichsheath has openings 52 in one side thereof, each of which registers with a respective hole 48. kEnd members 54 of electrically insulating material cover the ends of the body 44, and openings 56 therein register with sockets 46. The sheathing 50 preferably extends over the edges of end members 54 to assure full insulation over the entire surface of the body. Set screws 58 extend through openings 52 and into holes 48.

To attach any electrical conductor to the connector 48, it is necessary merely to bare a short length of wire at the end of the conductor and insert it fully into one of the sockets 46 so that the insulation behind the bare wire is disposed in the countersunk outer portion of the socket. Set screw y58 is then tightened against the wire to hold it securely attached to the connector. In this connection it will also be observed that screw :S forces the wire solidly against the metal body to assure va good electrical connection. As suggested, the supply lines 36 and connectors 46 are fastened in'the rough box and suitably connected before the latter is installed. When supply lines 36 and connectors 40 are disposed in the rough box in this manner, the latter is ready for mounting on a wall or ceiling and can be readily connected to the electrical supply circuit from the building either before or after the cover wiring is connected. In practice, it usually is advisable to make the supply lines 36 somewhat longer than the fixture sov that they can be extended through the open ends of the ducts for connection to the supply circuit or to an adjacent xture.

It will be observed that the connector here shown by Way of illustration provides three openings for attachment of conductors from the building supply circuit, from the adjacent fixture, or from the cover wiring. If only one cover is used on each rough box, three holes in all is sufcient to supply the lamp circuit and the adjacent unit; but, it will be readily apparent that even though all the sockets in the connector are not used, the open socket or sockets do not constitute a fire hazard nor are they in any way dangerous to .persons working on fixtures due to the completely insulated nature of the connector. It will also be apparent that, if necessary or desirable, the connector can be provided with a lesser or greater number of sockets than here shown.

In the drawings, the fixture is shown arranged crosswise of ceiling joists 60 and fastened thereto by nails 52 which are driven upwardly Since it is standard practice to place the joists of a building xed and predetermined distances apart, it is possible to construct the rough box so that the housings ID will accommodate the ballast and other electrical apparatus on the cover [and at the same time fit between the joists 60. It will be observed that when the rough box is mounted in this manner, only the projecting side Wall portions 24 and the side wall strip I4 extend from or below the joists 56, and that no part of the rough box projects below the plaster 64 or other wall-forming material on the joists.

Two covers 66 (Fig. 2) are arranged in end-toend relation on the rough box in the embodiment of the invention here shown. Manifestly, however, there is nothing critical in this feature, and the number of covers used in any particular instance depends upon the length of the tube lamps to be mounted thereon and the length of the rough box unit. These two covers 66 are idenyrough boxes.

tical and each carries two tube lamps 68 mounted side by side. Assuggested, the covers 66 preferably ,are made of sheet metal, are generally rectangular in form, and of a size to cover the open bottom of the rough box. The end portions of the covers are bent back upon themselves, as at lll, to eliminate sharp edges; moreover, the double. thickness of material reinforces and strengthens the covers and prevents them from warping or buckling under the weight of or heat from the lamps. Similarly, the side portions of thecovers 66 are bent :back upon themselves, as at l2, to provide reinforced side margins. As best shown in Figs. 4 6, these margins overlie the inturned iianges 32, 34 of the rough box and are detachably fastened thereto by screws 14. At the inner edges of inturned portions l2 are upstanding flanges 16 iwhich serve to guide the covers 66 into position on the rough box and at least partially to close the wiring ducts, as best shown in Figs. 4 and 5, when the covers are fastenedin place.

Mounted side by side at the ends of each cover 66. and fastened thereto by bolts 18 and nuts 86 is a pair of conventional lamp sockets 82 which suspend the tube lamps 68 in spaced parallel relation below the covers.

Flanges i6 also provide supports for a transverse bracket 86 Iwhich mounts the starter switches 88. Mounted on the back or inner side of the cover and positioned to fit into one of the box-shaped housings l() is a conventional ballast Sil. The sockets 82, starters 88, and ballast 99 on each cover 66 are wired in circuit with the lamps 68 in the conventional manner, and the circuit on each cover includes a pair of lead-in wires 92 (Fig. 8) which connect to respective supply lines 36 in the rough box through connectors 4U in the manner hereinabove described.

In addition to the above, means is provided for suspending the covers 66 from the rough box when they are detached so as to render the wiring and electrical apparatus readily accessible.

As shown in Fig. 6, hinge straps 9-4 are mounted on brackets v$36 which bridge and are fastened to the flanges 16. Any desired number of hinge straps may be provided on each cover 66, but two straps disposed adjacent opposite ends of the covers is usually sufficient. These straps 94 are arranged in planes normal to the plane of their respective covers 66, and they extend angularly therefrom through slots 98 in the housings I0.

It will be observed that the hinge straps 94 project substantially beyond the rough boX when the covers 66 are closed and that the projecting portions are disposed between the joists El) and behind the wall 64. Formed integrally on the ends of straps 94 are hooked portions |90 which intereng-age vwith the lower ends of slots 98 to hold the covers 66 and their adjuncts suspended from the roug'nbox as shown by dotted lines in Fig. 6.

It will be readily apparent that the electrical apparatus and other adjuncts are assembled on the covers before the latter are mounted on the Thus, the covers form complete subassemblies, and it is necessary merely to connect the two lead-in wires 92 to respective connectors 4! in order to provide a completely asn sembled fixture. When closed, the covers are disposed substantially flush with the wall or ceiling 64 and entirely conceal the rough box. The only exposed portions of the fixture are the covers 66, the projecting portions of sockets =82, and the tube lamp 68. vThe outer surfaces of atomes covers 66 may be polished and, if necessary or desirable, shaped in any suitable manner to provide a reflector for the tube lamps 68.

The utility and `adaptability of the -fixture are readily apparent from the foregoing description. Each fixture can be used as an individual unit in the lighting arrangement, or 'a number 'of them can be arranged end to end in any desired pattern to form a continuous strip lighting. This feature greatly expedites vcommercial installation where it frequently is necessary to use long rows of fluorescent lamps in order to obtain proper light distribution. Installation preferably is performed before the building walls and ceilings are finished and `the rough boxes, equipped with electrical supply lines and connectors, are fastened to the joists according to a predetermined plan or pattern. lSince all the rough boxes are identical, they may be picked at `random from vstoel: and used at any place in the pattern. This factor alone greatly facilitates and expedites installation. When installation is complete, the supply lines 3B in selected series -of rough boxes are connected together and to the electrical supply circuits in the building through connectors 40 in the manner hereinabove described.

Also, since the covers are identical and fully wired, except for connecting the two lead-in wires B2, they too can be selected at random from a stock supply and suspended indiscriminately from the rough boxes by their hinge straps 94. With the covers thus positioned, the wires 92 can be easily and quickly connected in the main circuit. *I'he covers are then raised and fastened by screws 18 to complete the installation.

In this connection it will be apparent that, if desired, the fixture can be adapted to suspend the tube lamps 6B. a desired. distance below the cover merely by mounting hanging supports thereon and fastening .the socket 82 on the suD- ports. Moreover, this can be done either before or after installation without removing or materially changing any part of the fixture.

Also, when a line of rough boxes are mounted along `a ceiling or wall yand electrically connected in series, it is possible to :change or alter the light distribution by mounting covers equipped with tube lamps and the .necessary adjuncts for supplying current thereto only onA certain of the rough boxes and fastening plain covers on the remaining boxes. Manifestly, a continuous circuit is provided by the rough boxes regardless of whether lamps are connected thereto. Furthermore, these changes can be made -at any time after installation and permit the lighting arrangement to be altered to meet changed o1 unsatisfactory conditions. Thus` the number of lamps can be increased or decreased at will. and wherever necessary to provide proper lighting.

It is to be understood that the form of the invention herewith shown and described is to be taken as a preferred example of the same and that various changes in the size, shape, and arrangement of parts may be resorted to without departing from the spirit of the invention or the scope of the appended claims.

Having thus described the application, I claim:

1. In a fluorescent lighting fixture, a rough box comprising an elongated boxlike sheet-metal housing having vertical slots in a Vside wall thereof, a longitudinal bottom opening in said housing, a plurality of longitudinally spaced channels extending transversely entirely across the top of the housing vand entirely separated from the interior of the housing, said channels opening upwardly and through both sides ofthe housing -so as to accommodate joists of a 4building, side strips forming wiring ducts extending from the bottoms of the-channels to the bottomof theA box and Yalong the longitudinal bottom edges of the housing for substantially the full length thereof, said ducts opening into the housing so that wires disposed therein are readily accessible through the bottom opening of the housing vand projecting -a slight distance below the bottom of said Vchannels so as to lie substantially flush with the plaster of a wall when the Ahousing is fastened to the joists of such wall with the joists in said channels, a separately formed cover -detachably fastened to said side strips and closing said bottom opening, mountings for fluorescent lamp means on the cover, electrical apparatus for supplying current through the iiuorescent lamp means including separate wiring in the 4housing and on the cover, and electrical connectors detachably and electrically connecting said separate wiring, means for connecting the wiring in said housing with an electrical supply circuit, and hinge strips on the cover extending through the slots in said housing, the projecting ends of said hinge strips having hook portions which interlock with the ends of the slots when the cover is detached from the housing and dropped so as to expose and render accessible said electrical apparatus.

2. .In a fluorescent lighting fixture, 'a rough box comprising an elongated boxlike sheet-metal housing, `a longitudinal bottom opening in said housing, a plurality of longitudinally spaced channels extending transversely entirely across the topy of the housing and entirely separated from the interior of the housing, said channels opening upwardly and through both sides of the housing so Vas to accommodate joists of a building, side .strips forming wiring ducts extending from the bottoms of the channels to the bottom of the box and for substantially the full length thereof, said ducts opening into the housing so that wires disposed therein are readily accessible through bottom opening of the housing and projecting a slight distance below the bottoms of said channels so as to .lie substantially flush with the plaster of a wall when the housing is fastened to the joists of such wall with thev joists in said channels, and a cover removably attached to the housing to close said bottom opening, the longitudinal marginal edges of said cover projecting laterally of said side stri-ps so as to overlie the wall plaster immediately adjacent the rough box.

3. In `a fluorescent lighting fixture, a rough box comprising an elongated boxlike housing, a longitudinal bottom opening in said housing, a plurality of longitudinally spaced channels extending transversely entirely across the top of the housing and entirely separated from the interior` of the housing, said channels opening upwardly and through both sides of the housing, and side strips extending along and secured to the longitudinal bottom edges of the housing for substantially the full length thereof, said side strips extending from the bottoms of the channels to the ybottom of the box, and a cover detachably fastened to said side strips closing said bottom opening.

4, In a fluorescent lightingk fixture, a rough box comprising a plurality of boxlilre members arrangedin spaced-apart series relation, each vof said boxlike members having top, side, and end waiis and Aari-'open bottom, connecting members extending between adjacent boxlike members, said members disposed adjacent and parallel to the bottoms of said boxlike members and fastened to the end walls thereof, sheetmetal strips `fastened to the sides of said boxlike members and extending substantially the full length of the rough box, said strips projecting below said end members to the bottom of the box and at least one of said strips being channel-shaped and open-ended to provide a runway for electrical supply lines.

5. In a fluorescent lighting fixture, a rough box comprising a plurality of boxlike housings arranged in spaced-apart series relation, each housing having top, side, and end walls and a bottom opening, connecting members joining said housings in a single integral structure, said connecting members having Webs bridging adjacent ends of the housings and portions fastened to the ends of the housings, said webs disposed adjacent to and substantially parallel with the bottoms of the housings, strips fastened to the sides of the housings and projecting between the web portions of said connecting members, and the bottom of the box at least one of said strips being channel-shaped and open-ended to provide a runway for electrical supply lines, and a cover detachably fastened to said strips closing the bottom openings of said housings.

6. In a fluorescent lighting xture, a rough box comprising a plurality of boxlike housings arranged in spaced-apart series relation, each housing having top, side, and end Walls and a bottom opening, connecting members joining said housings in a single integral structure, said connecting members having webs bridging adjacent ends of the housings and portions fastened to the ends of the housings, and said webs disposed adjacent to and substantially parallel with the bottoms of the housings and co-operating with the ends of the housings to define transverse channels for accommodating joists of a building when the box is mounted thereon.

TAGE KETELSEN.

REFERENCES CITED The following references are of record in the le of this patent:

UNITED STATES PATENTS Number Nan-le Date 1,224,971 Skinner May 8, 1917 1,943,660 Edwards Jan. 16, 1934 2,338,521 Levy Jan. 4, 1944 2,163,562 Putnam et al. June 20, 1939 2,182,434 Hobl Dec, 5, 1939 2,309,792 Schepmoes Feb. 2, 1943 2,321,099 Naysmith June 8, 1943 2,376,715 Naysmith May 22, 1945 

